What does the Windkessel effect do?

Large elastic arteries store a portion of the stroke volume with each systole and discharge that volume with diastole. This phenomenon, known as the windkessel effect, helps to decrease the load on the heart and to minimize the systolic flow and maximize diastolic flow in the arterioles (Dobrin, 1978).

Why do arteries recoil?

The elastic recoil of the arteries allows the artery to expand as normal but then exert an inward force to create blood pressure. The artery is slowly returning back to it’s original shape which is continually ‘maintaining’ pressure.

What is aortic recoil?

During recoil of the aortic wall, this potential energy is converted to kinetic energy, propelling the blood within the aorta to the peripheral vasculature. The volume of blood ejected into the aorta, the compliance of the aorta, and resistance to blood flow are responsible for the systolic pressures within the aorta.

What are resistance vessels?

A resistance artery is small diameter blood vessel in the microcirculation that contributes significantly to the creation of the resistance to flow and regulation of blood flow. Resistance arteries are usually small arteries or arterioles and include precapillary sphincters.

Does dilation increase blood flow?

Vasodilation refers to the widening, or dilation, of the blood vessels. It is a natural process that increases blood flow and provides extra oxygen to the tissues that need it most.

What are capacitance vessels?

Capacitance vessels are consid- ered to be the blood vessels that con- tain most of the blood and that can readily accommodate changes in the blood volume. They are generally considered to be veins.

What is a Windkessel vessel?

Windkessel when loosely translated from German to English means ‘air chamber’, but is generally taken to imply an elastic reservoir. The walls of large elastic arteries (e.g. aorta, common carotid, subclavian, and pulmonary arteries and their larger branches) contain elastic fibers, formed of elastin.

What causes the aorta to expand and recoil?

As the blood passes through the aorta, the pressure in this large artery increases, and the aortic walls elastically expand to accommodate the flowing blood. During diastole, the aortic walls recoil.

How does resistance affect blood flow?

Resistance is a force that opposes the flow of a fluid. In blood vessels, most of the resistance is due to vessel diameter. As vessel diameter decreases, the resistance increases and blood flow decreases. Very little pressure remains by the time blood leaves the capillaries and enters the venules.

What is resistance and capacitance vessels?

The resistance vessels include small arteries, arterioles, and precapillary sphincters. Capacitance vessels include small and large veins. Capacitance vessels have great capacity to distend. For a similar rise in pressure, capacitance vessels may accommodate 20 times more blood than resistance vessels.

What happens when blood vessels dilate?

What is vasodilation? Vasodilation is the widening of your blood vessels. It happens when smooth muscles found in the walls of arteries or large veins relax, allowing the blood vessels to become more open. This leads to an increase in blood flow through your blood vessels as well as a decrease in blood pressure.

What causes dilated blood vessels?

The term “vasodilation” refers to a widening of the blood vessels within the body. This occurs when the smooth muscles in the arteries and major veins relax. Vasodilation occurs naturally in response to low oxygen levels or increases in body temperature.

What is the Windkessel effect?

The term ‘Windkessel effect’ is used in the setting of large elastic arteries like aorta. The original term ‘Windkessel’ means ‘air chamber’ in German language. It was an air chamber used in fire engines in the 18th century, to maintain continuous delivery of water for fire fighting.

What is Windkessel effect in carotid artery aneurysm?

Windkessel effect may a play a role in larger internal carotid artery aneurysms which act as a capacitance chamber. Slow arrival of contrast distal to the aneurysm has been noted [3]. It has been postulated that loss of this effect after treatment of large aneurysms may place the distal cerebral circulation at risk of hemorrhage.

What is Frank’s Windkessel model?

Otto Frank (physiologist), an influential German physiologist, developed the concept and provided a firm mathematical foundation. Frank’s model is sometimes called a two-element Windkessel to distinguish it from more recent and more elaborate Windkessel models (e.g. three- or four-element and non-linear Windkessel models).

What is the Windkessel analogy?

The Windkessel analogy illustrated. Windkessel effect is a term used in medicine to account for the shape of the arterial blood pressure waveform in terms of the interaction between the stroke volume and the compliance of the aorta and large elastic arteries (Windkessel vessels) and the resistance of the smaller arteries and arterioles.